Splicing Footsteps

You can copy the motion of a biped footstep sequence, and paste it either at the end or into the middle of another footstep sequence. This technique is called splicing.

You can use splicing to build an extended, or cyclic, motion sequence out of shorter sequences. You can also copy footsteps from one biped and paste them onto another biped with this technique.

Splicing footsteps makes use of a footstep buffer to store footstep positions and keys. The buffer is a temporary area in memory where footsteps are stored.

TipUse motion splicing when you want to edit segments of a single footstep-based animation. To build longer animations by connecting finished BIP files, use Motion Flow or the Motion Mixer.

Procedures

To copy footsteps to the buffer:

Turn on (Footstep Mode).
Select a series of footsteps.
On the Footsteps Operations rollout, click (Copy Footsteps).

To edit the footstep buffer:

You can edit the footstep buffer only when footsteps have been copied to the buffer, as described in the previous procedure.

On the Biped rollout Modes group, click (Buffer Mode). This button is active only when there are footsteps in the buffer.
The viewports now display the footsteps in the footstep buffer, rather than the footsteps in the currently activated footstep sequence.
Edit footsteps or motion keys as you normally would – by moving and rotating footsteps, or turning on Auto Key and moving and rotating parts of the biped skeleton.
NoteYou can’t splice (copy and paste) footsteps while in Buffer mode.

If you load a BIP file by clicking Load File on the Biped rollout while Buffer mode is active, the footstep buffer is replaced with the motion in the BIP file.
Click Buffer Mode to turn it off.
Now you can splice the edited buffer by pasting footsteps.

To splice the footstep buffer:

On the Footstep Operations rollout, click (Paste Footsteps).
The footsteps from the buffer appear in their saturated colors.
Click (Select And Move) to position the first pasted footstep at the point where you want to splice. When you move the first pasted footstep over an activated footstep of the same side, right or left, the activated footstep turns red to indicate splicing is possible.
This step is usually easiest to do in a Top viewport.

NoteIf you deselect the pasted footsteps by clicking elsewhere in a viewport, no paste occurs and the pasting process ends.
When you have moved the buffer footsteps to the desired location, release the mouse.
The contents of the footstep buffer are placed over the active footsteps. The first footstep in the buffer replaces the footstep that turned red, and the rest of the buffer footsteps follow.
The footstep that turned red and the remaining original footsteps now appear in the viewports. They will be near the activated footsteps, in their saturated colors. They can now be moved and pasted onto the end of the spliced motion, which will, in effect, perform an insert of the buffer motion. The red footstep and is following footsteps can also be pasted anywhere in the footstep sequence. If you pasted onto the last footstep, this step does not occur.
If you don’t want to append the leftover footsteps, simply click anywhere in the viewport to dismiss them.

WarningIf any footstep in the buffer overlaps in time with a footstep previous to the one onto that you are pasting, a message appears and the paste will not be performed.

TipTo create a cycle of a motion with alternating footsteps, you must copy and paste at least three footsteps.